package com.changgou.file.util;

import com.changgou.file.pojo.FastDFSFile;
import org.csource.common.NameValuePair;
import org.csource.fastdfs.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.io.ClassPathResource;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;


public class FastDFSClient {

    private static Logger logger = LoggerFactory.getLogger(FastDFSClient.class);

    /**
     * 初始化加载FastDFS的TrackerServer配置
     */
    static {
        try{
            String filePath = new ClassPathResource("fdfs_client.conf").getFile().getAbsolutePath();
            ClientGlobal.init(filePath);
        }catch (Exception e){
            logger.error("FastDFS Client Init Fail!", e);
        }
    }

    /**
     * 文件上传
     * @param file
     * @return
     */
    public static String[] upload(FastDFSFile file){
        // 获取文件的作者
        NameValuePair[] meta_list = new NameValuePair[1];
        meta_list[0] = new NameValuePair("author", file.getAuthor());

        // 接收返回数据
        String[] uploadResults = null;
        StorageClient storageClient = null;
        try{
            storageClient = getTrackerClient();
            /**
             * 文件上传
             * 1)文件字节数组
             * 2)文件扩展名
             * 3)文件作者
             */
            uploadResults = storageClient.upload_file(file.getContent(), file.getExt(), meta_list);
        } catch (Exception e) {
            e.printStackTrace();
            logger.error("Exception when uploadind the file:" + file.getName(), e);
        }
        if (uploadResults == null && storageClient != null) {
            logger.error("upload file fail, error code:" + storageClient.getErrorCode());
        }
        // 获取组名
        // String groupName = uploadResults[0];
        // 获取文件存储路径
        // String remoteFileName = uploadResults[1];
        return uploadResults;
    }


    /**
     * 获取文件信息
     * @param groupName:组名
     * @param remoteFileName：文件存储完整名
     * @return
     */
    public static FileInfo getFiles(String groupName, String remoteFileName){
        try {
            StorageClient storageClient = getTrackerClient();
            return storageClient.get_file_info(groupName, remoteFileName);
        } catch (Exception e) {
            logger.error("Exception: Get File from Fast DFS failed", e);
        }
        return null;
    }

    /**
     * 文件下载
     * @param groupName
     * @param remoteFileName
     * @return
     */
    public static InputStream download(String groupName, String remoteFileName){
        try {
            StorageClient storageClient = getTrackerClient();
            byte[] bytes = storageClient.download_file(groupName, remoteFileName);
            InputStream inputStream = new ByteArrayInputStream(bytes);
            return inputStream;
        } catch (Exception e) {
            logger.error("Exception: Get File from Fast DFS failed", e);
        }
        return null;
    }

    /***
     * 获取Storage组
     * @param groupName
     * @return
     * @throws IOException
     */
    public static StorageServer[] getStoreStorages(String groupName)
            throws IOException {
        // 创建TrackerClient
        TrackerClient trackerClient = new TrackerClient();
        // 获取TrackerServer
        TrackerServer trackerServer = trackerClient.getConnection();
        // 获取Storage组
        return trackerClient.getStoreStorages(trackerServer, groupName);
    }

    /***
     * 获取Storage信息,IP和端口
     * @param groupName
     * @param remoteFileName
     * @return
     * @throws IOException
     */
    public static ServerInfo[] getFetchStorages(String groupName,
                                                String remoteFileName) throws IOException {
        TrackerClient trackerClient = new TrackerClient();
        TrackerServer trackerServer = trackerClient.getConnection();
        return trackerClient.getFetchStorages(trackerServer, groupName, remoteFileName);
    }

    /***
     * 获取Tracker服务地址
     * @return
     * @throws IOException
     */
    public static String getTrackerUrl() throws IOException {
        return "http://" + getTrackerServer().getInetSocketAddress().getHostString()
                + ":" + ClientGlobal.getG_tracker_http_port()+"/";
    }

    /***
     * 获取Storage客户端
     * @return
     * @throws IOException
     */
    private static StorageClient getTrackerClient() throws IOException {
        TrackerServer trackerServer = getTrackerServer();
        StorageClient storageClient = new StorageClient(trackerServer, null);
        return storageClient;
    }

    /***
     * 获取Tracker
     * @return
     * @throws IOException
     */
    private static TrackerServer getTrackerServer() throws IOException {
        TrackerClient trackerClient = new TrackerClient();
        TrackerServer trackerServer = trackerClient.getConnection();
        return  trackerServer;
    }

}
